The initial-final mass relationship of white dwarfs revisited: effect on the luminosity function and mass distribution

TL;DR

This study revises the initial-final mass relationship for white dwarfs by re-evaluating data, analyzing its dependence on parameters, and testing its impact on the white dwarf luminosity function and mass distribution, showing good agreement with observations.

Contribution

The paper provides a new semi-empirical initial-final mass relationship covering a broad initial mass range and analyzes its effects on white dwarf population characteristics.

Findings

The revised relationship fits observational data well.

Dependence on metallicity and rotation is suggested.

Results improve understanding of white dwarf mass distribution.

Abstract

The initial-final mass relationship connects the mass of a white dwarf with the mass of its progenitor in the main-sequence. Although this function is of fundamental importance to several fields in modern astrophysics, it is not well constrained either from the theoretical or the observational points of view. In this work we revise the present semi-empirical initial-final mass relationship by re-evaluating the available data. The distribution obtained from grouping all our results presents a considerable dispersion, which is larger than the uncertainties. We have carried out a weighted least-squares linear fit of these data and a careful analysis to give some clues on the dependence of this relationship on some parameters such as metallicity or rotation. The semi-empirical initial-final mass relationship arising from our study covers the range of initial masses from 1.0 to 6.5 M_sun, including in this way the low-mass domain, poorly studied until recently. Finally, we have also performed a test of the initial-final mass relationship by studying its effect on the luminosity function and on the mass distribution of white dwarfs. This was done by using different initial-final mass relationships from the literature, including the expression derived in this work, and comparing the results obtained with the observational data from the Palomar Green Survey and the Sloan Digital Sky Survey (SDSS). We find that the semi-empirical initial-final mass relationship derived here gives results in good agreement with the observational data, especially in the case of the white dwarf mass distribution.